This is competing continuation proposal for Years 17-22 of the Health and Retirement Study (HRS). We propose to continue core data collection on the steady-state design laid out in the previous renewal, including the addition of a new cohort in 2010;to build on our sub-study of prevalence of dementia to examine incidence;to add the collection of biological samples, including DNA, and psychosocial content;and to continue the use of mail surveys on special topics, including continued longitudinal measurement of consumption and time use for about half of the sample, as a low-cost complement to the core data collection. This proposal includes the period from January 1,2006 through December 31, 2011. HRS provides a uniquely rich, nationally representative longitudinal dataset for the community of scientific and policy researchers who study the health, economics and demography of aging. It provides a research data base that can simultaneously support cross-sectional descriptions of the U.S. population over the age of fifty, longitudinal studies of a given cohort over a substantial period of time and research on cross-cohort trends. By 2010 the HRS will be able to support cross-cohort comparisons of trajectories of health, labor supply, or wealth accumulation for persons who entered their 50'sin 1992, 1998 and 2004. The HRS project creates a data system extending beyond the core survey data. One component of this extended data system consists of linkages to administrative data, including Social Security earnings and benefit records, Medicare utilization and diagnostic records, employer pension records, and the National Death Index. We plan to expand these linkages to include information on nursing home residents from the Minimum Data Set and to explore linkages to Medicaid records. A second component is the use of the HRS survey as a sampling frame to support in-depth sub-studies targeted on specific diseases or topic areas. A third aspect of the HRS data system, which is not formally part of the HRS project, is the emergence of a set of longitudinal studies of aging in other countries which have been consciously designed to produce data as comparable as possible to that collected by the HRS. The HRS provides public use data designed to allow the full power and creativity of America's scientific community to address the challenges of an aging population. The HRS is making a significant impact on research on aging through investigator-initiated research which uses the HRS as an input without charge to researchers or granting agencies.